1. Technical Field
This invention relates to the art of containerization of goods and to the separate and independent arts of designing pallets (platforms for transfer of goods) and of transferring articles by robotic handling.
2. Description of Prior Art
Factory-of-the-future concepts will require automated transfer of goods in hybrid units that integrate functions, only some of which are found separately in shipping containers or in transfer pallets. The functions essentially comprise: (a) containerizing and protecting surface-delicate goods; (b) positioning such goods for accurate mechanical transfer; (c) versatile realignment of the container interior to accept varying sizes of goods; and (d) modularizing such containerization to fill standardized cargo space.
Pallets are movable platforms that provide a flat surface upon which goods are supported and have channels to receive arms of a forklift vehicle for transport. The pallets can be constructed from a variety of materials, including metal, molded plastics, or wood (see U.S. Pat. Nos. 3,691,965; 4,564,109). Wooden pallets are popular because of their economy, but fail to provide containerization or protection for the goods. They are readily damaged through use and must be discarded which imposes a difficult disposal problem. Most importantly, they fail to provide precision positioning of the goods as demanded for robotic transfer.
Shipping containers comprise an active art that has included clustering a plurality of goods within a casing while providing some form of good-to-good separation. The containers can be made from a variety of materials just like the pallets. Often, the good-to-good separation is provided by cardboard dunnage, discardable after use, causing an environmental disposal problem. Much of the advancement in containerization for elongated goods, such as shafts or rods, has come from industries dealing with dangerous cargo such as missiles, rocket motors, or nuclear rod assemblies (see U.S. Pat. Nos. 2,457,262; 4,666,035; 3,369,973; 4,594,216; 3,643,812). In the '262 patent, woods spacers are deployed within a metal shell to protect the rocket motors contained therein, but the entire structure must be dismantled to remove the articles, which does not lend itself to quick and accurate access for robotic transfer. In the '035 patent, plastic dunnage was deployed for separating and protecting explosive shells or missiles, the dunnage in turn being held together by a wire assembly. Although this construction provides for easy stacking and clustering of the articles for transportation, there is certainly no provision for precise handling and pickup in a robotic transfer environment.
In Soviet Union patent publication 1,312,009, a container was disclosed for enclosing a plurality of shafts, allowing the shafts to roll into indexable positions within the container locked in place by turnable separators, the shafts are similarly removed from the container by gravity, rolling out an end of the container with the separators moved to a neutral position. Such container design does not provide for protection that is needed for surface-delicate goods such as previously machined camshafts or crankshafts; the rolling contact would damage such surfaces. Moreover, if such containers ere to be stacked one upon the other, the loads transferred between containers would not be independent of the goods or articles within the container and thus would not provide the kind of protection needed for robotic handling.